Reasons for not hosting here

So There is always a chance of Power outage or Internet connection problems...
I have been testing my mail server for the past few weeks and I dont want to host it in my office, due to these problems.

And moreover I need to take regular backups and maintain everything.

What I wanted is a solution where, I dont have to worry about the power or internet problems, and if the hosting provider is already having Zimbra Hosting then, it would be much easier to do the Administration and Maintanence.

I am not able to decide which company to select from,as they are not providing the exact plan details, rather they are providing more information about the zimbra partnership and the zimbra features.

I am looking for the features of the hosting provider. as I already know the features of zimbra

If there isn't enough information in the Partners page then I can only suggest that you contact them directly. I can't speak for Zimbra directly but I don't think they would announce any partners before they've signed up or announced their service so I guess you're stuck (for the moment) with the current list.

I did some searching with Google on "hosted Zimbra" about a month a half ago, not much out there, tried again about a week ago and found about 15 different hosting companies that were either offering or going to offer Zimbra.